Annealing properties of open volumes in HfSiOx and HfAlOx gate dielectrics studied using monoenergetic positron beams

Thin Hf0.6Si0.4Ox and Hf0.3Al0.7Ox films fabricated by metal-organic chemical-vapor deposition and atomic-layer-deposition techniques were characterized using monoenergetic positron beams. Measurements of the Doppler broadening spectra of annihilation radiation and the lifetime spectra of positions indicated that positrons annihilated from the trapped state by open volumes that exist intrinsically in amorphous structures of the films. For HfSiOx, the mean size of the open volumes and their size distribution decreased with increasing postdeposition annealing (PDA) temperature. For HfAlOx, although the overall behavior of the open volumes in response to annealing was similar to that for HfSiOx, PDA caused a separation of the mean size of the open volumes. When this separation occurred, the value of the line-shape parameter S increased, suggesting an oxygen deficiency in the amorphous matrix. This fragmentation of the amorphous matrix can be suppressed by decreasing the annealing time.

[1]  A. Uedono,et al.  Characterization of Hf0.3Al0.7Ox Fabricated by Atomic-Layer-Deposition Technique Using Monoenergetic Positron Beams , 2004 .

[2]  T. Nabatame,et al.  Roles of nitrogen incorporation in HfAlOx(N) gate dielectrics for suppression of boron penetration , 2004 .

[3]  K. Torii,et al.  Effect of Hf Sources, Oxidizing Agents, and NH3/Ar Plasma on the Properties of HfAlOx Films Prepared by Atomic Layer Deposition , 2004 .

[4]  A. Uedono,et al.  Characterizing Metal-Oxide Semiconductor Structures Consisting of HfSiOx as Gate Dielectrics using Monoenergetic Positron Beams , 2004 .

[5]  W. D. Wang,et al.  Thermal stability of (HfO2)(x)(Al2O3)(1-x) on Si , 2002 .

[6]  John Robertson,et al.  Band offsets and Schottky barrier heights of high dielectric constant oxides , 2002 .

[7]  Alfredo Pasquarello,et al.  Dielectric constants of Zr silicates: a first-principles study. , 2002, Physical review letters.

[8]  A. Uedono,et al.  Study of oxygen vacancies in SrTiO3 by positron annihilation , 2002 .

[9]  M. J. Kim,et al.  Boron penetration studies from p+ polycrystalline Si through HfSixOy , 2002 .

[10]  Eduard A. Cartier,et al.  Physical and electrical characterization of Hafnium oxide and Hafnium silicate sputtered films , 2001 .

[11]  Eduard A. Cartier,et al.  Materials characterization of ZrO2–SiO2 and HfO2–SiO2 binary oxides deposited by chemical solution deposition , 2001 .

[12]  R. Wallace,et al.  High-κ gate dielectrics: Current status and materials properties considerations , 2001 .

[13]  T. Ohdaira,et al.  A positron lifetime spectroscopy apparatus for surface and near-surface positronium experiments , 2000 .

[14]  G. Molnár,et al.  Oxidation/reduction effects on the thermoluminescence of α-Al2O3 single crystals , 2000 .

[15]  B. Nielsen,et al.  Metal ion and oxygen vacancies in bulk and thin film La{sub 1{minus}x}Sr{sub x}CoO{sub 3} , 1999 .

[16]  B. Nielsen,et al.  VACANCY DEFECTS IN (PB, LA)(ZR, TI)O3 CAPACITORS OBSERVED BY POSITRON ANNIHILATION , 1998 .

[17]  K. Lynn,et al.  Characterization of defects in Si and SiO2−Si using positrons , 1994 .

[18]  Roger B. Gregory,et al.  Analysis of positron annihilation lifetime data by numerical Laplace inversion: Corrections for source terms and zero-time shift errors , 1991 .

[19]  R. Wallace,et al.  Hafnium and zirconium silicates for advanced gate dielectrics , 2000 .

[20]  B. Nielsen,et al.  Identifying open-volume defects in doped and undoped perovskite-type LaCoO{sub 3}, PbTiO{sub 3}, and BaTiO{sub 3} , 2000 .

[21]  R. Krause-Rehberg,et al.  Defect Characterization in Elemental Semiconductors , 1999 .

[22]  O. Mogensen,et al.  Program system for analysing positron lifetime spectra and angular correlation curves , 1984 .